Supercritical carbon dioxide (scCO2) is used to prepare novel silica aerogel composites containing nano-particles of palladium. The material produced has been found to exhibit a Pd loading of 8% by wt. The particles deposited fit within two discrete size ranges of 2 may be successfully applied to prepare catalytic support materials based upon aerogels and that the catalyst is active in a continuous flow reactor leading to effective hydrogenation of cyclohexene.